Mercury-vapor electric converter



Dec. 7, 1948. R. NEIRYNCK MERCURY VAPOR ELECTRIC CONVERTER Filed Feb. 24, 1948 Patented Dec.7, i948 :1 i

N TEDS TE i MERCURY-VAPOR. ELEofritiocoNvERT R TitogeBNeIrynck, Mont-sur-MarchiennefBelgium, assignor to Societe anonyme dite: Ateliers de 1 Constructions Electriques de Charleroi, BrusselsilBelgium;aoompany ofBelgium. i i

.ihpplicationFebruary 24, 1948, Sel ial No. 10,32 p i In France March 29, 1943 H V i Section ljPublicLaw 690, August s, 1946 i i i Patent expires March 29, 1963 i s oisims. (01. 250-215) The present inventionrelates to improvements conduit leading such gases to the rectifier, inac in mercuryvapor electric converters particularly cordance with the molecular flowing laws of gases in the means and methodi'orwemoving excess at very low pressures... u i

vapor pressure fromthe converter. With the above and other objects in view which When mercury vapor converters are operated willbecome apparent from the detailed descripvvithout a pump it has been observed that such tion below, the invention is set forth in the folconverters have the property of reabsorbingth'e lowing description, claimed in the claims and gases disengaged during operationi However shown in the drawings, inwhlch:

when the apparatus operates temporarily at a Fig. 1 illustrates schematically one form of the higher chargethan that for whichit has been invention and, i

designed the gas disengaged "during" such. opera- Fig. 2. illustratesschematically a modified form tion will exceed the gas reabsorbed. In suchcase of the invention. the density of the gaslin the converter increases Referring to the drawings in which like parts and as a result thereof operationaltroublessuch are designated by similar reference characters, as back-fires or relating diflicuities will arise in t tank f th mer ury vapor converter is shown a short time. This excessof'gas produced during 1 t I. A high vacuum mercury por P p is the period of v rch r ng ,1 i quite disadconnected at its suctionside to the tank I by the vantageous in that the reaction will be present CI1d11it 3 and at its pressure S 50 a reservoir for a considerableperiody'lfhis is because dur- 4 by a conduit 5. A conduit I P v ed with a ing overcharge the recombination processes of valve 8 connects the reservoir 4 to the tank I of the gases withcertain internal elements of the the converter.

converters, such as mercuryvapor is accelerated. In accordance with the invention theses P d- The increased production of these recombination nets in excess during overcharge operation of the e converter, 1 a: t

products is disadvantageous for the operation of converter are suctioned by the high vacuum pump X i i 1 2 [and stored in thereservoir 4. Since no point For the above reasons it is highly desirable to of the pumping circuit is at atmospheric pressure withdraw the excess gas from the tank during itisnot necessary provide a prel minary vacthe period of overcharging. uum pump of the paddle type and the pump 2 An object of the inventionis to remove from may be formed as a mercury vapor pumpwith the rectifier an excess accumulation of gas dur- 3o twostages. i

ing certain periods of operation and then re- The valve 8 positioned in the circuit of the store such gas to the rectifier during periods of conduit I connecting the reservoir 4 to the tank normal pressure, so that such gas may be reabl of the converter is controlled in such a way sorbed. that the return of the suctioned gases can not A further object of the invention is to provide take place before the converter return-s to normal a separate reservoir into which excess gas may operation.

be pumped from the rectifier and then returned The valve 8 may be controlled by a motor 9 gradually from such reservoir to the rectifier throu h a ntr l arran u j t d t when conditions have become normal. the influence of a calculable size which varies A still further object of the invention is to closely with the pressure of the gases liberated provide means in such separate reservoir whereby in the converter enclosure. the gases pumped therein may be wholly or par- For example this control factor may be: tially fixed, i a. The interior pressure of the tank of the A still furtherobject of the invention is to converter wherein the pressure is measured by provide means whereby the return of the excess a vacuum meter of the Wheatstone bridge type. gases from the reservoir to the rectifier may be or aPirani gauge.

controlled by a value which in turn, is controlled e intensity of the rectified current traveither by the internal pressure existing within ersing the converter, which may be measured the converter or by the charging rate or by raiseither by a shunt placed in the circuit for the ing the temperature from a determined point of continuous current or by an intensity transformthe converter. er located in a phase of the alternating current A still further object of the invention is to procircuit. vide means whereby the return of excess gases 0. The elevation of the temperature reached in from the reservoir to the rectifier is controlled service by a determined point on the metallic tank by suitable length and cross-sectional area of the be and this elevation in temperature may be meas- Knudsen formula:

3 ured by a thermocouple and the point chosen on the tank may be located in a zone adjacent the arc, for example in the-bottom of the tank.

These factorsmay be used indifferently either the one or the other considerin their interdependence.

A modified form of the invention is shown in V Fig. 2 of the drawing in which the conduit I and Q is the estimated flow by multiplying the pressure in a given section by. the volume of gas traversing :such'section in one second.

P1 and P2 are the pressuresiatthe two ends of the conduit. J 1 is the'flovv resistance obtained from. the

. a V? .15 W=-.- ix/2r 7 Wherein p is the density of the as at the temperatureof the conduitand at the pressure there existent,

a L is the length of the conduit, and

isits radius (inthe case of a=-cylindrical conduit).

Therefore,.in accordance with .the various forms of the inventionset forth above when the density of the gases in the converter reaches a normal value at the-termination. of the overcharging Iperiod and because of the action of. the pump 2 the gases stored in the reservoir :4 itemporarily may return without any inconvenience tothe converter. 1

Furthermore if desired certain products may beplaced in the intermediary reservoir 4 which .willfix the gases either whol y .or partly. Products of this type may be: bases for acid gases, sulphuric acid, or phosphorous pentoxide for water vapor. Also for this purpose the reaction products of alkaline metals with harmful gases 4 under the action of an electric discharge may be used.

f 1'. A' mercury vapor 'jeonverter comprising a rectifier, a reservoir for excess gas, a high vacuum pump interposed between said rectifier and said reservoir for withdrawing excess as from said rectifier and forcing said gas into said reservoir 7 and-means for returning said gas from said reservoirgto saidrectifier operable during periods of normal operation of said rectifier.

2. A mercury vapor converter comprising a rectifier, a reservoir for excess gas, a high vacuum pump, interposed between said rectifier and said reservoir for withdrawing excess gas from said rectifier and forcin said gas into said reservoir,

ma-conduitconnecting said reservoir and said "rectifienza :reservoirior excess gas, :a high vacuum pump interposedbetween said rectifier and said reservoir for Withdrawing excessgas from said rectifier and forcingsaid ega-s into-said reservoir, a conduit connecting said reservoir and said rectifier to return excess gas from said reservoir to said rectifien'said conduitbeing of such length and such cross-sectional area that the return of gas to said' rectifier takes place only during operation of said rectifier.

4. A method of operating amercury vapor electric converterl-comprising removing excess gas pressure from "said converter during overcharging periods and returning said gas to said converter during normal operation periods. v

5. A-method of operating a-mercury vapor electric converter com-prising reducing the vapor density of the mercury, vapor during overcharging periods by withdrawing excess gas from. the converter and storing said excess gas in an auxilia-ry reservoir fixing a plition of said excess gas within said reservoir and then returning said excess-848 from saidreservoir-to said converter during normal periods of operation of said converter. I p

' ROGER NEIRYNCK.

, 1 No referencescited. 

